Basic Information
| Field | Details |
|---|---|
| Full name | Zachary Paul Koehn |
| Approximate birth year | Circa 1989 |
| Birthplace | California |
| Adoption and upbringing | Adopted as an infant by a Mennonite family; raised in northeast Iowa near St. Ansgar and McIntire |
| Education | Mennonite school; completed eighth grade at age 14 |
| Religious status | Expelled from Mennonite faith at age 16 for drinking and smoking |
| Substance history | Began using methamphetamine around age 17 |
| Pre-2017 residence | Riceville and Alta Vista, Iowa |
| Occupation | Long-haul truck driver hauling chickens for Nugent Nuggets |
| Work schedule and pay | 70 to 80 hours per week; approximately 45,000 dollars annually |
| Partner | Cheyanne Renae Harris (not married) |
| Children | One daughter from a prior marriage; two children with Harris, including Sterling Daniel Koehn |
| Criminal convictions | First-degree murder and child endangerment resulting in death (2018) |
| Sentence | Life in prison without the possibility of parole |
| Incarceration | Iowa Department of Corrections |
| Appeals | Convictions upheld in 2020 |
Early Life and Mennonite Roots
Zachary Paul Koehn was born in California and adopted by a strict Mennonite family before moving to rural northeast Iowa. Traditions included simple living, catholic schooling, and a close-knit community where eighth grade ended formal education.
Koehn finished Mennonite school at 14. The seams broke two years later. Being ejected from the Mennonite church at 16 for drinking and smoking was more than just a break. A trajectory was set. Family accounts say he started using methamphetamine at 17 and continued throughout his adulthood.
Family and Personal Relationships
Koehn’s family network is anchored in his adoptive Mennonite household and extends through relationships that produced several children. He did not remarry after his first marriage ended, and his long-term partnership with Cheyanne Harris was not formalized.
Family Map
| Relation | Name and details |
|---|---|
| Adoptive father | Willis Koehn, Mennonite background; testified about upbringing; later moved to Oklahoma |
| Adoptive mother | Name not publicly disclosed |
| Siblings | Older brother Danny Koehn; two additional siblings not publicly named |
| Ex-wife | Name not publicly disclosed; one daughter from this marriage |
| Partner | Cheyanne Renae Harris, born circa 1997 to 1998; two children with Koehn; convicted in 2019 of the same offenses |
| Children | Daughter from prior marriage, born circa 2010, living with Koehn’s adoptive parents in Oklahoma; daughter with Harris born circa 2015; son Sterling Daniel Koehn born circa April 2017 and deceased August 30, 2017 |
A rigid upbringing and early substance abuse were reported by family members. Brother Danny worried about the kids’ care, especially considering Koehn’s long road trips. In his home with Harris, he worked long shifts and she did most of the babysitting.
Worklife on the Road
From Wisconsin to Charles City, Iowa, Koehn drove Nugent Nuggets chickens significant distances. The position earned $45,000 per year and required 70 to 80 hours per week, enough to support a family with health insurance. He had early departures, overnight hauls, and recovery time between runs.
His trial defense hinged on this grind. He claimed he worked away from home and trusted Harris as the primary caregiver. Prosecutors argued that the household was not poor and had child care services. The road that paid the bills hid the warning lights, but they were later claimed to be visible.
The Death of Sterling Daniel Koehn – August 30, 2017
On August 30, 2017, at the family’s Alta Vista apartment, 4-month-old Sterling Daniel Koehn was found unresponsive in a baby swing in a hot, dark bedroom. Koehn dialed 911. What first responders and investigators uncovered quickly evolved into a case of extreme neglect.
The autopsy revealed significant starvation and dehydration. An E. coli infection from a diaper that hadn’t been changed in 9–14 days. There were maggots. According to the facts, neglect occurred over time. During this time, the couple’s oldest daughter was clothed and fed.
Investigation, Trials, and Verdicts 2017 to 2020
The parents were arrested and charged soon after Sterling’s death. Legal proceedings shifted venue to Henry County.
- 2017: Arrests followed the discovery of Sterling’s death. Charges included first-degree murder and child endangerment resulting in death.
- 2018: At his trial, Koehn testified that he relied on Harris for primary caregiving while he maintained a punishing work schedule. The jury convicted him on November 6. A December 4 sentencing hearing imposed the mandatory penalty of life in prison without parole.
- 2019: Harris was tried separately. She was convicted and received a life sentence without parole.
- 2020: The Iowa Court of Appeals upheld Koehn’s convictions. No subsequent public legal activity has been reported.
The verdicts reflected the court’s conclusions about parental responsibility, causation, and the level of neglect. The weight of the evidence, measured in days, conditions, and medical findings, carried through trial and appeal.
Media Presence and Public Profile
Koehn has no personal social media or interviews for public consumption. Trial footage, podcasts, and online debates review the timeline and forensic evidence in true-crime media. Some local news recaps highlight case anniversaries, while Court TV and trial video include testimony and closing arguments. No public statements, filings, or family interviews have occurred since the 2020 appeal ruling.
Extended Timeline
| Year or date | Event |
|---|---|
| Circa 1989 | Born in California; adopted as an infant by a Mennonite family |
| Early childhood | Family relocates to St. Ansgar and McIntire area of northeast Iowa |
| Circa 2003 | Completes eighth grade at age 14 |
| Circa 2005 | Expelled from Mennonite faith at age 16 |
| Circa 2006 | Begins using methamphetamine at around age 17 |
| Pre-2014 | Marries, has a daughter, later divorces |
| 2014 | Meets Cheyanne Renae Harris in Riceville, Iowa |
| Circa 2015 | Daughter with Harris is born |
| Circa April 2017 | Son Sterling Daniel Koehn is born |
| August 30, 2017 | Sterling is found deceased in the family apartment |
| 2018 | Koehn convicted and sentenced to life without parole |
| 2019 | Harris convicted and sentenced to life without parole |
| 2020 | Appeals court upholds Koehn’s convictions |
| 2021 to present | Incarcerated in the Iowa Department of Corrections |
Key Numbers at a Glance
| Metric | Number or range |
|---|---|
| Work hours per week | 70 to 80 |
| Annual income | About 45,000 dollars |
| Sterling’s age at death | About 4 months |
| Estimated diaper interval | 9 to 14 days |
| Children | Three total: one from a previous marriage, two with Harris |
| Age milestones | Eighth grade at 14; expelled from faith at 16; meth use begins around 17 |
| Conviction year | 2018 |
| Sentence | Life without parole |
| Appeals status | Upheld in 2020 |
Family Snapshot
- Adoptive parents: Willis Koehn and an unnamed mother from a Mennonite background. Willis later moved to Oklahoma.
- Siblings: Danny Koehn spoke publicly, with two additional siblings not named in records.
- Ex-wife: Name not disclosed; one daughter from that marriage lives with Koehn’s adoptive parents.
- Partner: Cheyanne Renae Harris, met in 2014, two children with Koehn, convicted in 2019.
- Children: Daughter from prior marriage born circa 2010; daughter with Harris born circa 2015; son Sterling Daniel Koehn born circa April 2017 and deceased August 30, 2017.
FAQ
Who is Zachary Paul Koehn?
He is an Iowa man convicted in 2018 of first-degree murder and child endangerment resulting in death in connection with his 4-month-old son’s death.
What happened to Sterling Daniel Koehn?
Sterling died on August 30, 2017, with medical findings of severe malnutrition, dehydration, and infection linked to a diaper not changed for 9 to 14 days.
What is Koehn’s sentence?
He received a mandatory sentence of life in prison without the possibility of parole.
Who is Cheyanne Harris?
She was Koehn’s long-term partner and Sterling’s mother, convicted in 2019 of the same offenses and also sentenced to life without parole.
Did Koehn have a job and steady income?
Yes, he worked 70 to 80 hours per week as a long-haul truck driver, earning about 45,000 dollars annually.
Did the appeal change the outcome?
No, the Iowa Court of Appeals upheld his convictions in 2020.
Does Koehn have other children?
Yes, he has a daughter from a previous marriage and a daughter with Cheyanne Harris.
Is there recent news about Koehn?
Public attention remains focused on true-crime recaps and archived trial coverage, with no new legal developments since 2020.
